I'm not sure he will. In fact right now, I'll reiterate my belief that he will not. He may figure it's best to wait until 2028 when there will be no more Trump or Biden.What makes you think that DeSantis wants to challenge Trump? Sounds like a good way for the fellow to lose and forfeit a chance to win in 2028 or 2032.
Right now, for the next year, all of the focus is going to be on the Trumpster. Its impossible for any other candidate to get traction without having a spotlight on them.
If I were advising Haley, or any other prospective candidate, I'd tell them to back down as well.
So far, his testing of the waters has been somewhat of a failure. Trump has managed to land a lot of punches on him and Ron has come off as whiny and weak-kneed.
None of the other Republicans have a chance against Trump. Pence, Haley, Pompeo, whomever. They are all out before Super Tuesday.